Foraminoplasty at the Tip or Base of the Superior Articular Process for Lateral Recess Stenosis in Percutaneous Endoscopic Lumbar Discectomy: A Multicenter, Retrospective, Controlled Study with 2-Year Follow-Up

Table 2

Changes of preoperative and postoperative VAS scores of low back pain .

Time point	Pre-operation	1 months postoperatively	3 months postoperatively	6 months postoperatively	1 year postoperatively	2 years postoperatively
Group A	5.1±0.7	3.2±0.6	2.5±0.8	2.1±0.4	1.6±0.3	1.5±0.4
Group B	5.0±0.9	3.0±0.7	2.8±0.6	2.0±0.3	1.7±0.5	1.4±0.5

VAS: visual analogue scale.